Pipeline Safety:
Awareness & Damage Prevention

Click
here for phone numbers to report a natural gas leak, suspicious
activity or any other pipeline emergency 24 hours a day, seven days
a week.

QUESTAR: BRINGING ENERGY HOME SAFELY AND RELIABLY FOR OVER 75 YEARS

At Questar, we take safety seriously. Since its
founding in 1929, Questar and its affiliates have engaged in every phase
of natural gas service — from production and gathering to transportation
and distribution. During that time, while delivering the clean and efficient
natural gas our customers rely on daily for their comfort and livelihood,
we have earned an enviable record for safety and reliability

Questar's 23,000 miles of gathering, transportation and distribution
lines are part of a 1.5-million-mile national underground pipeline network.
Most Americans are totally unaware of this vital transportation system
that delivers the energy that drives our economy.

Questar's operations, and those of other pipeline companies, are overseen
and regulated by the United States Department of Transportation's (DOT)
Office of Pipeline Safety (OPS) and its state partners. Under standards
imposed by DOT, Questar and other pipeline companies together invest millions
of dollars each year in training and new technology designed to monitor
and continually improve the safety and integrity of their pipelines. These
companies also conduct public outreach programs to increase awareness
about pipeline safety, as well as potential hazards and how to avoid them
through proven damage-prevention practices. The result, according to government
statistics, is the safest transportation system in the nation today. Questar
and others in the pipeline industry are committed to maintaining and strengthening
this reputation for safety.

PIPELINE SAFETY IS BUILT IN

The DOT imposes rigorous standards for pipeline
design, construction, maintenance, testing and operation. Questar's policies
and procedures are designed to meet and, in most cases, exceed these standards.
Our commitment to safety begins before a pipeline is built or expanded.
We build safety into our system by:

carefully researching and planning the safe construction of each
project;

using pipe that is inspected and tested at the factory to comply
with both federal and industry standards;

providing steel pipe with a coating and other measures that protect
it from external corrosion;

inspecting the integrity of the pipe during construction;

testing the finished pipeline at pressures higher than normal operating
pressure before it's placed into service;

SAFETY IS MAINTAINED DURING OPERATION

Once a pipeline is built, tested and placed in
service, Questar controls and monitors the safety of its system in several
ways, including:

posting markers with emergency telephone numbers along our rights of way to let the
public know underground pipelines are in the area;

routinely patrolling our pipeline routes on the ground and from
the air to inspect and identify potential problems and assist in preventing
third-party excavation damage;

performing regular inspection and maintenance of facilities, including
leak surveys and safety-device checks on valves and compressor stations;

meeting periodically with state and local emergency officials to
review accident-prevention and emergency-response procedures;

monitoring our system using computers and remote telemetry equipment
that detects changes in pressure or flow that might indicate problems.
In many cases, such equipment also allows operators to quickly activate
emergency shut-down procedures and to dispatch emergency crews in
case of a leak, accident or other problem;

performing periodic internal inspections on some pipeline sections
using "smart pigs" — mechanical devices that travel inside pipelines,
checking for anomalies or weaknesses in the pipe that could cause
failure.

QUESTAR AND THE PUBLIC: PARTNERS IN PIPELINE
SAFETY

America's natural gas pipeline industry maintains
an enviable record of safety and reliability. However, despite strict
federal oversight and the conscientious efforts of companies like Questar,
hazards do exist and emergencies, though infrequent, can occur. Statistics
show that the majority of pipeline damage is caused by third parties (construction
contractors, property owners, excavators, etc.) digging near buried pipelines.
Third-party damage can be prevented by using local excavation notification
systems known as One-Call.

CALL BEFORE YOU DIG: USE ONE-CALL SYSTEMS

In the states where Questar operates, the law
requires anyone planning to dig or excavate near an underground pipeline
to notify a local One-Call Center two working days (48 hours) before beginning
work. The One-Call center will notify member utilities that operate buried
facilities in the area. A utility representative will determine if the
project is near underground facilities and dispatch someone to the work
site to clearly mark the route and location of buried cables and/or pipelines.

Questar owns and operates underground pipelines in Utah, Idaho, Wyoming,
Colorado, Arizona, New Mexico and California and participates in the following
One-Call Centers:

LOCATION
OF EXCAVATION

NAME
OF ONE-CALL CENTER

TOLL-FREE NUMBER

Arizona

Arizona Blue Stakes

800-782-5348

California

Underground Service Alert Of California

800-227-2600

Colorado

Utility Notification Center Of Colorado

800-922-1987

Idaho

Dig Line

800-342-1585
208-342-1585

New Mexico

New Mexico One-Call System

800-321-2537

Utah

Blue Stakes Center

800-662-4111
801-208-2100

Wyoming

One-Call of Wyoming

800-849-2476

NATURAL GAS LEAKS: RECOGNITION AND RESPONSE

Natural gas pipeline leaks or failures are rare,
but an informed public can help prevent emergencies and minimize potential
damage or injury in the unlikely event of an accident by knowing how to
recognize and report pipeline problems.

How to identify a leak

The following signs may indicate a natural gas
pipeline leak or failure:

a hissing, roaring or blowing sound

dirt being blown into the air

water being blown into the air at a pond, river or creek

continuous bubbling in wet, flooded areas

fire at or near exposed piping

flames apparently emanating from the ground

dead or brown vegetation in an otherwise moist or green field

a "rotten egg" odor (Note: In its natural state, natural gas is
odorless, as well as colorless and non-toxic. Local utilities such
as Questar Gas add a non-toxic chemical odorant called mercaptan to
its supplies to make leaks easy to detect by smell. However, odorants
are usually added to pipelines only in populated areas, so leaks,
especially in open country, cannot always be detected by smell.)

What to do if a leak occurs

Follow these steps if you discover natural gas
escaping from a broken or leaking line:

turn off all machinery and vehicles and prevent other sources of
ignition such as open flames and the operation of electrical switches
or cellular phones

evacuate everyone from the endangered area and keep vehicles and
bystanders away

do not attempt to make any repairs or operate any pipeline valves

do not attempt to extinguish any fire

from a safe place, notify Questar to report a leak or other natural
gas emergency by calling the emergency numbers listed below.

call 911 or otherwise notify your local emergency response agency
such as fire department or law enforcement

How to Locate a Natural Gas Pipeline

For public-safety reasons, most pipelines are
buried several feet underground. To make pipelines easier to locate and
identify, Questar companies install markers near roads and highways, at rail and river crossings and at other locations
along our rights of way. These markers show a pipeline's approximate location
and provide emergency-contact telephone numbers. Not all buried lines,
especially lower-pressure distribution lines, have markers. Therefore,
to more accurately determine the location of pipelines in your area, especially
before digging or performing any excavation, contact a local One-Call
line-location agency listed above.

Maps showing the general locations of pipelines owned and operated by
Questar companies can be seen by clicking on the following links:

A list of pipelines in the United States, including a directory that
identifies pipeline operators in any given area by entering a Zip Code,
can be found on the Web site of the DOT's National Pipeline Mapping System
at www.npms.rspa.dot.gov/ .

Web sites for One-Call centers in states where Questar companies operate
can be found using the following links:

The Interstate Natural Gas Association of America (INGAA) is an excellent
source of information on pipelines and pipeline safety in particular and
the natural gas industry in general. INGAA's Web site can be found at www.ingaa.org.
Additional information about the natural gas industry is provided by the
American Gas Association at www.aga.org.